Refrigerating apparatus



Julv 1, 1924. I A 1,499,489

R. W. TIBBETTS REFR IGERATI NG APPARATUS Filed July 1919 5 Shams-sheet 1 July 1 1924.

1,499,489 R. W. TIBBETTS REFRIGERATING APPARATU Filedduly 5, 1919 s Sheets-Sheet 2 Mari l July 1 1924. I R. W. TIBBETTS REFRIGERATING APPARATUS Filed July 5, 1919 3 Sheets$heet I Watcnted duly 'i, W24.

hthtl REFRIGERATING APPARATUS.

Application filed July 3, 1919. Serial No. 308,397.

To all 3117mm it may concern:

Be it known that I, RAYMOND W. TIB- snrrs, a citizen of the United States, residing at Pawtucket, in the county of Provilift dence and State of Rhode Island, have invented certain new and useful Improvements in Refrigerating Apparatus, of which the iollowin is a' spec fication, reference being had tiorein to the accompanying drawings.

This invention relates to refrigerating apparatus in which air is compressed and expanded, in succession, and 1n the narrower view, the object is to provide apparatus especially suited for domestic or small scale use, and havin characteristics of construction specially ntting it for such use. Accordingly, in the drawings, the invention is illustrated as embodied in apparatus of that description, in which drawings,

Fig. 1 is a side elevation thereof;

Fig. 2 is a vertical section;

Fig. 3 is an end elevation partly in sec tion; and

Fi 4 is a detail view of the ice-preventing" evice.

llhe apparatus comprises an air compres sion cylinder placed horizontally on top of the refrigerator, or food receptacle 11, and an expansion cylinder 12 with its axis extending at a right angle to that of the compression cylinder, and reaching down into the refrigerator compartment 13, through a hole in the top thereof and which is closed by the bed of the apparatus. Since the expansion. cylinder becomes cold when till tltl

the apparatus is in operation, its location within the refrigerator is very advantageous, since for some time after cessation of operation of the apparatus, the cold cylinder walls or parts absorb heat and thus keep down the temperature in the refrigerator.

The compression cylinder piston 14- and the expansion cylinder piston 15 are com nected by connecting rods 16 and 17, respectively, to a crank pin 18 on a motor driven disk 19, the arrangement being such that the expansion cylinder delivers a maximum of power at the time the compression cylinder is using a maximum of power, and thus work on the motor is reduced. The crank disk is on a shaft 20 having a sprocket wheel 21 connected by a chain 22 with a sprocket wheel 23 on the armature shaft of an electric motor 2i. dllheswitch of the name operated by a thermostat (not shown) so that the motor only runs when the temperature in the refrigerator is above the degree desired to be maintained in the refrigerator.

In the head of the compression cylinder is an air inlet port 25 having a valve 26 opened by suction of theiston, and an eduction port 27 controlled y a valve 28, lifted from its seat by pressure from the piston on its compression stroke. Air is supplied to the inlet port by a pipe 29 having an air filter 30 containing charcoal, or some other deodorizer or airpurifying medium, which filter may be located in the refrigerator as shown, to draw warm air therefrom, or outside, or both inside and outside. With the eduction port is connected one end of a pipe coil 31, whose other end is connected to a port or passage 32 in the opposite end of the compression cylinder dcr that leads to the induction port 33 in the head 34 of the expansion cylinder. The induction port 33 is controlled by a valve 35 that is opened and closed periodically by a lever 37 that acts on the valve stem 38 and is connected to one end of rod 39 whose other end is connected with an eccentric ring 40 in one side of the crank disk and thereby a to-and-fro movement is imparted to the rod. The eduction port 41 in the head of the expansion cylinder is controlled by a valve 42 that likewise is opened and closed by a lever 13 that acts on the valve stem 44; and besides its straight line motion said exhaust valve 12 has a rotary motion, produced by a ratchet wheel 45 on the stem and a pawl 46 that engages the ratchet wheel teeth and receives its motion from the lever 43 to which it is attached. Below the valve 42, and quite close to it when seated, is a circular series of radially extend: ing teeth, or pointed pins 45, which coact with the valve when it moves, to break up any ice tending to form from moisture in the air, on the adjacent surfaces of, the ex haust, and which it formed, chokes up the exhaust. Said pins may be attached to the the reirigertor diminishes the like ihood of formation of ice by fleecing moisture in the und the compression cyder s a were space or jacket, whichlopcnshtc which is journalled a roller 53 that rests on the upper run of the sprocket chain ,When the motor is not running the slack of the chain allows the weight to desmnd far enough to close the valve, but when the motor runs, the upper run of the chain'becomes taut, andlifts the weight and the valve handle enough to open the valve and allow flow of water to the water space.

The operation of the machine will be evident from the description thus far given, and briefly, is as follows: When the temperature in the refrigerator is above the limit desired, the thermostat will start the motor, and theupper slack run of the chain 22 being tightened, the water controlling valve Wlll be opened, thus supplying water to circulate through the water space and about the coil, to cool the compression cylinder-and the air. Purified air is alternately sucked into and expelled from the compression cylinder and forced into and through the coil, and thence into the expansion cyl inder, from which in an expanded and temperature lowered state it exhausts directly into the refrigerator. The relative volumes of compression and exhaust cylinders are such that pressureis built up and main-.

tained in the pipe (.Oil, and hence the latter is both an air container and an air cooling means, since it is enveloped by the circulating water. As soon as the desired low temperature is attained in the refrigerator, the thermostat automatically stops the motor.

The machine shown is very small and compact, not liable to get out of order, is inexpensive to rnn,.and produces a very low I emperature.

Of course, changes may be made from the construction shown, and, hence the scope of the invention is not to be restricted to the particular; construction and arrangement of a parts. shown, beyond the requirements of the language of the claims and having regard to the law as to equivalents.

What is claimed is l. A' refrigerating apparatus of the class described having means for compressing and expanding air, the air expanding means having a cold air exhaust port and automatic means for dislodging ice from such port.

2. A refrigerating apparatus of the class described having means for compressing and expanding air, the air expanding means hav ing a cold air exhaust port and automatic means for .dish'idging ice from such port con iprisiug spaced teeth in such port and a coo 'ieratin member.

3. A i-el i-igerating apparatus of the class described having means for compressing and expanding air. the air expanding means having a cold air exhaust port and automatic means for dislodging ice from such port comprising a movable body in the port and spaced teeth in such port with reference to which such body moves.

4. A refrigerating apparatus oi the class described having means for compressing, and expanding air, the air expanding means having a cold air exhaust port and automatic means for dislodging ice from such port comprising spaced teeth in such port and a valve moving with reference to and cooperating with said teeth.

5. A refrigerating apparatus of the class described having means for compressing and expanding air, the air expanding means hav-- ing a cold air exhaust port, a valve to control such port, means to reciprocate and rotate the valve, and spaced teeth in the port adjacent the valve.

6. A refrigerating apparatus having a cylinder with a n'lOtOF-(lllYQIi piston, a motor, a fluid supply pipe having a valve, motor-eontrolled means to open and close the valve comprising an endless transmitting band a -.|.uated by the motor, and a part connected with the movable member of the valve resting in contact with one of the band runs, said hand run being slack when the motor is not operating and allowing movement of the movable valve member to close the valve.

In testimony whereof I afiix my signature.

' RAYMOND W. TIBBETTS. 

